This first episode of the season, produced by Fred Freiberger, introduces Maya to the regular cast. On the planet Psychon, an evil-minded alien named Mentor captures the Alphans and tries to drain their minds. His daughter Maya who is capable of transforming herself into any form, helps the Earth people to escape. [NOTE: later re-edited into the first half of the movie Cosmic Princess.]

Moonbase Alpha is invaded by hostile living rocks. John Koenig, Helena Russell and Maya must battle time and an army of strange alien life forms that can communicate, transport themselves and attack unsuspecting Alphans with deadly rays of coloured light.

The Alphans come upon a fleet of missile-like objects that imprison the frozen bodies of exiles from another planet, and rescue two innocent-looking young aliens who turn out to be psychopathic killers.

Two aliens discovered sealed in a chamber beneath the moon's surface are released from suspended animation. They then begin to infect the Alphans with a mysterious disease that causes outbursts of violence.

Because of Maya's accidental "murder" of some flowers on a strange planet ruled by highly intelligent plant life, she and John Koenig must stand trial and engage in mortal combat with three horrifying aliens who committed a similar "crime."

A travelling trader of the universe covets Maya in return for a device that could transport the Alphans back to Earth.

THE BETA CLOUD
Writer: Charles Woodgrove (aka Fred Freiberger).
Director: Robert Lynn.
Guest Cast: Dave Prowse.
Many Alphans are already mysteriously incapacitated when they are further menaced by a huge creature in a space cloud sent by another planet to steal their life-support system.

Her powers disturbed by a mysterious disease, Maya loses control over her metamorphic powers, changing from one creature to another. Meanwhile, Koenig is separated light years from Alpha when the moon travels through a strange space warp, and Moonbase Alpha inhabitants are afflicted by sudden madness.

A "Superswift" spaceship from Earth arrives to rescue the Alphans, but an experimental machine enables Koenig to perceive the apparent rescuers for what they really are: horrifying aliens intending to destroy the moon.

The Alphans send Maya to infiltrate the ranks of alien warriors who are posing as rescuers from Earth. Conclusion of a two-part story. [Both parts later re-edited into the movie Destination: Moonbase Alpha.]

THE LAMBDA FACTOR
Writer: Terrance Dicks.
Director: Charles Crichton.
Guest Cast: Debra Fallander (Carolyn Powell), Jess Conrad (Mark Sanders).
The appearance of a cosmic cloud coincides with the mysterious death of a young woman and nightmares experienced by Koenig, transforming one of moonbase Alpha's women into a megalomaniac with strange super powers.

The disintegration of their Eagle spacecraft traps John, Alan and a critically injured Tony on a planet they were exploding. As they are stranded on the nearby planet, they discover that they are being stalked by an alien and that they are now the prey of unknown creatures.